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Systematic Study of Low-Cost, High-Performance Chemical Flooding as EOR for Depleted Oilfields of the Upper Assam Basin
Published in Subrata Borgohain Gogoi, Advances in Petroleum Technology, 2020
Miranda Kakoty, Subrata Borgohain Gogoi
The principal limitation of most chemical flooding is adsorption of surfactants on the reservoir rock surface. As the clay of porous media of the Upper Assam Basin is negatively charged [39], an anionic surfactant is preferred. The porous media repels the anionic surfactant and thus shows low adsorption effects. This led to the selection of anionic surfactants for the porous media of Upper Assam. BL is a highly toxic compound and can cause severe health hazards to humans and poses a threat to aquatic life if disposed of without treatment. Thus, prior to discharge, it must undergo proper treatment, which, in turn, has high financial implications. Therefore, proper strategic use of BL for surfactant EOR may not only provide economic recovery of residual oil but also save the environment from its hazards. Figure 6.1 shows the IFT behaviour of crude oil with BL, and Fig. 6.2 shows the IFT behaviour of the oil sample with different surfactant mixtures, each containing BL. The reservoir temperature of the Barail sand block is reported as 70°C–90°C. The CMC is the concentration at which the surfactant solution begins to form micelles in a large amount and all additional surfactants added to the system go to micelles.
Clinical Applications of Spectral Computed Tomography
Published in Katsuyuki Taguchi, Ira Blevis, Krzysztof Iniewski, Spectral, Photon Counting Computed Tomography, 2020
Micelles are consisting of a monolayer of surfactants compared to the bilayer of phospholipids that define liposomes. They are therefore significant smaller (2–20 nm) compared to liposomes that can vary in size (20 nm–3 μm) and tend to have a hydrophobic core enabling the transport hydrophobic molecules in a hydrophilic environment compared to liposomes that can transport hydrophobic materials in between the two layers of the phospholipids and hydrophilic drugs in their core or cavity. Micelles occur naturally in the digestive tract and help to resorb otherwise non-soluble molecules. They are therefore attractive for alternative ways of drug or potential contrast agent delivery – including oral application. One of the main advantages is the relative simple and cost effective production of this nanoscale-delivery system. They have already been used for the delivery of alternative contrast agents like Bismuth into targeted structures and the resulting enhancement could be reliable detected in actual tumor tissues (16).
Dispersion Techniques of Nanoinclusions in Cement Matrixes
Published in Antonella D’Alessandro, Annibale Luigi Materazzi, Filippo Ubertini, Nanotechnology in Cement-Based Construction, 2020
The presence in their structures of both polar and nonpolar portions leads to easy solubilization of these molecules both in polar (such as water) and nonpolar solvents. The increase of their concentration in solution leads to a self-aggregation process; this reduces the interactions between the solvent and the differently structured portions, leading to micelle formation [43, 44]. This phenomenon occurs at a concentration that is specific for every surfactant, which is called critical micellar concentration (CMC). This value depends on the structural features of the surfactant, particularly on its hydrophobicity. Micelles are nanoscaled spherical aggregates of molecules of surfactants that are spontaneously formed in order to reduce the contacts between the hydrophobic portions and water or between the hydrophilic portions with apolar solvents. In Fig. 2.4 are reported the structures of a micelle (surfactants in water) and of a reverse micelle (surfactants in apolar/hydrophobic solvents).
Surface-active natural saponins. Properties, safety, and efficacy
Published in International Journal of Environmental Health Research, 2023
Essential criteria for cleaning products are the capability of micelles to form as they can emulsify the contaminant that would otherwise be insoluble. More specifically, we have demonstrated that QS possesses the lowest CMC (.1 mg mL−1) followed by EC (.5 mg mL−1) and SA (.6 mg mL−1), while SDS is less effective in forming the micelle (1.5 mg mL−1). Furthermore, Jarzębski et al. (2020) found that the CMC varies concerning extraction method between .1 and 1.5 mg mL−1 for Quillaja saponaria extracts, while Ribeiro et al. (2013) found CMC at .2 mg mL−1. However, Alpandi et al. (2021) studied the saponin surface tension and found CMC at .5 mg mL−1, which corresponds to our findings. The findings of the current study are consistent with those of Góral and Wojciechowski (2020), who reported that the CMC for escin is between .3 and .4 mg mL−1. Moreover, Motin et al. (2015) demonstrated CMC for sodium dodecyl sulphate at 2 mg mL−1, which is a bit higher in comparison to our results.
Synergistic interaction of α-olefin sodium sulfonate/cocamidopropyl betaine surfactant mixtures and preparation of wormlike micelles
Published in Journal of Dispersion Science and Technology, 2023
Penghui Li, Jianghong Wu, Shengti Cao, Yanfen Mao, Yueqing Huo, Xiaochen Liu
In order to reduce the free energy of the system, surfactants can self-assemble into various aggregates in aqueous solution, such as spherical micelles, rod micelles, wormlike micelles, vesicles, hexagonal liquid crystals and layered liquid crystals.[10] The continuous growth of spherical micelles along one-dimensional direction can form worm-like micelles with lengths of hundreds of nanometers or even several micrometers. The wormlike micelles can be entangled with each other to form a flexible network structure, and the micelles and monomers can be dissociated and recombined continuously, which is also known as "living polymer", which also gives worm-like micelles special rheological behavior.[11] Worm-like micelles have broad application prospects and can be used in tertiary oil recovery, clean fracturing fluids, drilling fluids, sustained drug release and so on.[12–14]
Synthesis and properties of sodium isotridecyl polyoxyethylene ether sulfate with different ethylene oxide addition numbers
Published in Journal of Dispersion Science and Technology, 2022
Penghui Li, Shengti Cao, Yueqing Huo, Xiaochen Liu
As a functional fine chemical product, surfactant is widely used in washing products,[1] cosmetics,[2] textiles[3]and tertiary oil recovery,[4] and so on, and has the reputation of “industrial monosodium glutamate.” Surfactants are composed of two parts, a lipophilic hydrocarbon chain part and a hydrophilic group, forming an asymmetric structure, also known as an amphiphilic compound. The special molecular structure allows it to be adsorbed on the two-phase interface, and form micelles in the solution, thereby reducing the surface tension and interfacial tension. Due to their different structures, surfactant molecules have a series of different properties such as solubilization, emulsification, dispersion, wetting, foaming, and washing.